We never learn his real name, only aliases, but gradually a picture is built of an intelligent, careful man who suffered an unhappy childhood surrounded by religious mania.

Not that the author wants us to feel sympathy - and we don't; we want this too-slick murderer to slip up.

He targets families in closed religious communities and we follow him as he moves in on his latest victims.

This hunting ground and his methods have proved foolproof to date, especially given his ability to change his appearance and control every situation. But this time the past is about to catch him up.

Redemption begins with two young brothers bound and gagged in a boathouse.

Years later, Detective Inspector Carl Mørck of Section Q, Copenhagen's cold case division, receives a bottle fished out of the sea off Scotland.

It contains an old and decayed message written in blood from the boys. But who were they and why weren't they reported missing?

Mørck, who also features in Adler-Olsen's earlier novels Mercy and Disgrace, is battling his own demons.

One colleague was left dead and another a quadriplegic in a shootout that Mørck survived.

His motley bunch of colleagues are also enough to drive any man to distraction.

For the reader, though, the grumpy Rose (and her peculiar sister) and secretive Syrian Assad are both engaging characters and their interactions provide some of the lighter moments.

Adler-Olsen likes to strip his characters psychologically and that's what makes Redemption so interesting.

We come to understand the killer in part, but never take his side. We want him stopped. We want Section Q to come to the rescue in time.

The chapters following this character as he plans another crime are compelling. Those involving Section Q are less interesting initially but the writer draws the story together nicely through the later stages.

The title Redemption is curious: Does it refer to Mørck's guilt over what's happened to his colleagues? Or do the killer's actions have deeper motives linked to childhood guilt?

Regardless, this is a fascinating Scandinavian crime novel. It's nicely paced for the most part and definitely a pace turner with a hard-edged psychological underbelly.